constexpr iterator<false> end()
requires ((!__simple_view<First> || ... || !__simple_view<Vs>) &&
__cartesian_product_is_common<First, Vs...>);
| (1) | (since C++23) |
constexpr iterator<true> end() const
requires __cartesian_product_is_common<const First, const Vs...>;
| (2) | (since C++23) |
constexpr std::default_sentinel_t end() const noexcept; | (3) | (since C++23) |
Returns an iterator or a sentinel representing the end of the cartesian_product_view.
Let bases_ be the underlying tuple of views.
__is_const be true for the const-qualified overload, and false otherwise; __is_empty be true if the expression ranges::empty(rng) is true for any rng among the underlying ranges except the first one and false otherwise; and __begin_or_first_end(rng) be expression-equivalent to __is_empty ? ranges::begin(rng) : __cartesian_common_arg_end(rng) if rng is the first underlying range and ranges::begin(rng) otherwise. Equivalent to:
auto check = [](auto& rng) { return __begin_or_first_end(rng); };
return iterator<__is_const>(__tuple_transform(check, bases_));return std::default_sentinel;.(none).
An iterator to the element following the last element, or a sentinel which compares equal to the end iterator.
Can be checked online with Compiler Explorer.
#include <array>
#include <print>
#include <ranges>
#include <string_view>
#include <tuple>
using namespace std::literals;
int main()
{
constexpr auto a = std::array{ "bool"sv, "goto"sv, "extern"sv, "long"sv }; /*
^ ^ ^ ^ */
constexpr auto v = std::ranges::cartesian_product_view(a[0], a[1], a[2], a[3]);
constexpr std::tuple<char const&,
char const&,
char const&,
char const&> last { *(v.end() - 1) };
std::println("{}{}{}{}",
std::get<0>(last),
std::get<1>(last),
std::get<2>(last),
std::get<3>(last));
}Output:
long
|
(C++23) | returns an iterator to the beginning (public member function) |
|
(C++20) | returns a sentinel indicating the end of a range (customization point object) |
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